Oval tube tires have been developed with carcasses that include a substantially flat crown on which replaceable circular tread and/or track belts are mounted. Such an oval tube tire is described fully in U.S. Pat. No. 3,606,921 which issued to C. E. Grawey and typically employs a plurality of circular ridges or ribs on the outer circular periphery of the carcass with matching circular grooves on the inner periphery of the circular belt that cooperatively mate with the ribs of the carcass when the belt is assembled on the flat crown. Because of this interlocking configuration between the tire carcass and the belt, the belt is very difficult to change or remove. Removal of the belt is further complicated by the fact the sidewalls of the tube carcass are stiff, by comparison to the central portion of the flat crown, so they tend to maintain their height even though the central portion of the flat crown of the carcass is collapsed inwardly thus freeing only the engagement of the ribs and grooves in the center of the crown while the top edges of the sidewalls remain engaged with the belt. Therefore, it can be appreciated that belt removal remains a problem because of the interference of the belt with the tops of the sidewalls of the carcass.
A manufacturing technique of drawing a vacuum inside a beaded tire is shown in U.S. Pat. No. 1,707,014, issued to Hopkinson wherein a convex crown is partially collapsed to fit an undersized tread on the outer periphery of this tire carcass. However, this manufacturing technique cannot be successfully applied to the oval tube tire for changing replaceable belts because of its substantially flat crown and stiff sidewalls, in comparison to the central portion of the crown.
In view of the above circumstances, it is an object of this invention to provide a simple and expedient method for removing and replacing tread or track belts on oval tube tire carcasses.